FAMILY TABANIDAE: SUBFAMILY TABANINAE 275 



2. Rings of the third antennal joint so distinctly divided that the 



antenna appears as if six- jointed ...... Hexatoma. 



Rings of third antennal joint not so distinctly divided ; the 



antenna always appears as if three jointed . ... . ~- . 7~"~ . 3 



3. Wings marked with rings and circles of darker colouring . . HaematopoJa. 

 Wings not so marked ........... 4 



Wings dark with light markings, but without the characteristic 



streaks of Haematopota Hippocentrum. 



4. First and second antennal joint in the male pubescent ; third 



joint longer than the first. Eyes hairy .... Dasybasis. 



5. First antennal joint globular situated on a protuberant pro- 



jection of the forehead Boldodim via. 



First joint of antenna not globular ......... 6 



6. Third joint of antenna simple, not furnished with a tooth or 



angular projection ........... 7 



Third joint of antenna furnished with a tooth or distinct 



angular projection ........... 9 



7. Body covered with metallic scales ...... Lepidoselaga. 



Body metallic in colouring ....... Selasoma, 



Body without metallic scales or colouring ; the first antennal 



joint longer than is usual in Tabantis ; wings usually with 



brown markings ............ 8 



8. Antenna long, the third joint cylindrical and situated on a 



projecting tubercle ........ Udenocera. 



Antenna short, Tabanus-like, situated on a prominent 



tubercle . Neotabanus. 



Antenna not very long, the third joint not cylindrical, and not 



situated on a projecting tubercle ...... Diachlorus. 



9. Abdomen short, stout and very convex ..... Stibasoma. 

 Abdomen neither short, stout or convex . . . . . . . . 10 



10. Antenna long and slender, the first joint long . . . Acanl hoccra. 

 Antenna neither long or slender, nor is the first joint long . . . . 11 



11. Species of a slender build, usually with a banded thorax and 



abdomen ; third joint of antenna slender, mostly with brown 



markings on wings ........ Dichelacera. 



Species of a stouter build ; third joint of antenna stout . . Tabanus (sens, lat.) 



In the above key three Ethiopian genera, Thaumastocera, Holoceria 

 and Parahaematopota, recently erected by Grunberg, have been omit- 

 ted, as each contains only one species. According to Grunberg the genus 

 Thaumastocera (T. akwa, Griin.) is separated from the South Ameri- 

 can genus Stibasoma by the curiously shaped third segment of the 

 antenna, which has two deep notches in its superior margin in the 

 female ; in both sexes the angle at the base ( superior ) is extended into 

 a process which extends as far as the end of the joint. Holoceria (H. 

 nobilis, Grim.) and Parhaematopota are closely allied to Haematopota, 

 and are considered by Austen to be of doubtful validity. H. nobilis has 

 the general facies of a Haematopota, but is without the characteristic 

 streaks and circles of white on the wings. The thorax is dark, with two 



